POS0322 CARDIOVASCULAR RISK FACTORS AND RISK OF GIANT CELL ARTERITIS AND/OR POLYMYALGIA RHEUMATICA: RESULTS FROM THE FRENCH E3N COHORT STUDY
Authors: F. Barde, C. Macdonald, C. Salliot, S. Ascione, F. Artaud, X. Mariette, M.C. Boutron-Ruault, Y. Nguyen, R. Seror
Journal: Annals of the Rheumatic Diseases (2022)

<h3>Background</h3> Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are two associated inflammatory diseases with incompletely known common pathophysiological mechanism. Cardiovascular (CV) risk factors have been thought to play a role in the underlying chronic vascular inflammation involved in GCA and PMR pathophysiology. However, available data on CV risk factors are conflicting. <h3>Objectives</h3> To investigate the association between CV risk factors and the risk of GCA and/or PMR in a large prospective cohort of French women. <h3>Methods</h3> The E3N cohort study (<i>Etude Epidémiologique auprès des femmes de la Mutuelle générale de l'Education Nationale</i>) is a French prospective cohort including 98,995 French women born between 1925 and 1950, recruited in 1990. They completed biennially mailed questionnaires to update their health-related information. A validation study based on the use of a specific GCA/PMR questionnaire and medication reimbursement database was conducted prior to this study. The history of CV risk factors (hypertension, type 2 diabetes, dyslipidemia, active smoking status and family history of cardiovascular disease) was self-reported at each questionnaire. Hazard ratios (HRs) and their 95% confidence intervals (95%CIs) for incident GCA and/or PMR were estimated by Cox proportional hazards regression models with age as the time scale. Multi-adjusted models included all CV risk factors and educational level. Further analyses were conducted to separately analyse the risk of incident GCA and of PMR. <h3>Results</h3> The overall population included 79,804 women, during a total follow-up of 1,899,742 person-years. Among them, 399 incident GCA and/or PMR cases were identified (incidence 31/100,000 person-years): 282 PMR alone, 112 GCA cases, and 5 patients who could not be classified. Incident GCA/PMR cases were diagnosed after a mean of 17.9 (± 5.2) years after recruitment. Mean age at diagnosis was 69 (± 7.2) years. Type 2 diabetes was inversely associated with risk of incident GCA/PMR in age-adjusted and multivariable models (HR 0.41; 95%CI 0.2–0.9 in multivariate model). Other CV risk factors such as hypertension, smoking status, dyslipidaemia, familial history of cardiovascular events were not associated with incident GCA/PMR (Table 1). The inverse association remained statistically significant when studying separately the risk of incident PMR (HR 0.3; 95%CI 0.09–0.91) but no longer with incident GCA (HR 0.5; 95%CI 0.1–2.0), probably due to a reduced statistical power. <h3>Conclusion</h3> Type 2 diabetes was associated with a decreased risk of subsequent GCA/PMR development. Further work should be carried out to determine potential mechanisms, and especially to analyze the respective role of diabetes itself and its treatments. <h3>Acknowledgements</h3> The authors are indebted to all participants for their continued participation. The authors would like to thank Pascale Gerbouin-Rerolle, Mariam Alyaniakian, Sofiane Harizi and Roselyn Rima Gomes for their help on data management. The present work was performed using data from the Inserm E3N cohort and support from the MGEN, Gustave Roussy, and the Ligue contre le Cancer for setting up and maintaining the cohort. The cohort was supported by a state grant ANR-10-COHO-0006 from the Agence Nationale de la Recherche within the Investissement d'Avenir program. The present work was conducted thanks to a research grant from the Agence Régionale de Santé – Île de France.ledgements to declare. <h3>Disclosure of Interests</h3> None declared